formaldehyde
noun
form·al·de·hyde
fȯr-ˈmal-də-ˌhīd 
fər-
: a colorless pungent irritating gas CH2O used chiefly in aqueous solution as a disinfectant and preservative and in chemical synthesis
Examples of formaldehyde in a Sentence
Recent Examples on the Web
Relaxers and chemical straighteners, touted for their easy-to-manage outcomes, saw a decline in use as more people learned about formaldehyde, a key ingredient in relaxer products and a carcinogen.
—
Leah Asmelash, CNN Money, 28 Feb. 2026
The nonprofit Southern Environmental Law Center has said gas turbines produce pollution and release hazardous chemicals, including formaldehyde.
—Bracey Harris, NBC news, 26 Feb. 2026
Researchers have found carcinogens -- including formaldehyde -- in the products, which are aggressively marketed to Black women and largely unregulated.
—Shaun Boyd, CBS News, 25 Feb. 2026
Mammals and reptiles were commonly treated with formalin before being stored in alcohol, while invertebrates were often preserved directly in formaldehyde or mixed solutions containing additives such as glycerol or propylene glycol.
—Neetika Walter, Interesting Engineering, 9 Feb. 2026
See All Example Sentences for formaldehyde
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Leah Asmelash, CNN Money, 28 Feb. 2026
The nonprofit Southern Environmental Law Center has said gas turbines produce pollution and release hazardous chemicals, including formaldehyde.
—Bracey Harris, NBC news, 26 Feb. 2026
Researchers have found carcinogens -- including formaldehyde -- in the products, which are aggressively marketed to Black women and largely unregulated.
—Shaun Boyd, CBS News, 25 Feb. 2026
Mammals and reptiles were commonly treated with formalin before being stored in alcohol, while invertebrates were often preserved directly in formaldehyde or mixed solutions containing additives such as glycerol or propylene glycol.
—Neetika Walter, Interesting Engineering, 9 Feb. 2026
See All Example Sentences for formaldehyde
Cite this Entry
“Formaldehyde.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/formaldehyde. Accessed 7 Mar. 2026.
Copy CitationKids Definition
formaldehyde
noun
form·al·de·hyde
fȯr-ˈmal-də-ˌhīd
fər-
: a colorless gas that consists of carbon, hydrogen, and oxygen, has a sharp irritating odor, and when dissolved in water is used to disinfect or to prevent decay
Medical Definition
formaldehyde
noun
form·al·de·hyde
fȯr-ˈmal-də-ˌhīd, fər-
: a colorless pungent irritating gas CH2O used chiefly as a disinfectant and preservative and in chemical synthesis
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